English verb conjugation
COULD GNAW

Regular verb: gnaw - gnawed - gnawed

Affirmation

Simple form	V-ing form
I could gnaw you could gnaw he could gnaw we could gnaw you could gnaw they could gnaw	I could be gnawing you could be gnawing he could be gnawing we could be gnawing you could be gnawing they could be gnawing
Perfect	V-ing perfect
I could have gnawed you could have gnawed he could have gnawed we could have gnawed you could have gnawed they could have gnawed	I could have been gnawing you could have been gnawing he could have been gnawing we could have been gnawing you could have been gnawing they could have been gnawing

Negation

Simple form	V-ing form
I couldn't gnaw you couldn't gnaw he couldn't gnaw we couldn't gnaw you couldn't gnaw they couldn't gnaw	I couldn't be gnawing you couldn't be gnawing he couldn't be gnawing we couldn't be gnawing you couldn't be gnawing they couldn't be gnawing
Perfect	V-ing perfect
I couldn't have gnawed you couldn't have gnawed he couldn't have gnawed we couldn't have gnawed you couldn't have gnawed they couldn't have gnawed	I couldn't have been gnawing you couldn't have been gnawing he couldn't have been gnawing we couldn't have been gnawing you couldn't have been gnawing they couldn't have been gnawing

Interrogative form

Simple form	V-ing form
could I gnaw? could you gnaw? could he gnaw? could we gnaw? could you gnaw? could they gnaw?	could I be gnawing? could you be gnawing? could he be gnawing? could we be gnawing? could you be gnawing? could they be gnawing?
Perfect	V-ing perfect
could I have gnawed? could you have gnawed? could he have gnawed? could we have gnawed? could you have gnawed? could they have gnawed?	could I have been gnawing? could you have been gnawing? could he have been gnawing? could we have been gnawing? could you have been gnawing? could they have been gnawing?

Interro-negative form

Simple form	V-ing form
couldn't I gnaw? couldn't you gnaw? couldn't he gnaw? couldn't we gnaw? couldn't you gnaw? couldn't they gnaw?	couldn't I be gnawing? couldn't you be gnawing? couldn't he be gnawing? couldn't we be gnawing? couldn't you be gnawing? couldn't they be gnawing?
Perfect	V-ing perfect
couldn't I have gnawed? couldn't you have gnawed? couldn't he have gnawed? couldn't we have gnawed? couldn't you have gnawed? couldn't they have gnawed?	couldn't I have been gnawing? couldn't you have been gnawing? couldn't he have been gnawing? couldn't we have been gnawing? couldn't you have been gnawing? couldn't they have been gnawing?